2.11. Animal Procedures
ApoE-deficient (ApoE-/-) mice with a C57BL/6J genetic background were provided by HFK Bioscience (Beijing, China). All mice were raised under specific-pathogen-free (SPF)-conditions and had free access to a standard purified mouse diet and water. All experiments were conducted in accordance with the institutional guidelines of Harbin Medical University. To observe the effect of CTRP9 on atherosclerosis in mice, 6-week-old male ApoE-/- mice were randomly divided into the following two groups: AAV-CTRP9 and AAV-control. The adeno-associated vector expressing CTRP9 and the negative control were synthesized by GenePharma (Shanghai GenePharma Co., Ltd., Shanghai, China). To deliver AAV, the mice were administered 1011 vector genome copies of AAV-CTRP9 or AAV-control via a single tail vein injection. Thereafter, the mice were fed a Western diet (21% fat and 1.25% cholesterol; Research Diets D12108C, New Brunswick, NJ, USA) for 8 weeks. After removing the adventitia and endothelium, the media of the aortic wall homogenates were used for western blotting. For histology, the aortic roots were embedded in OCT compound or paraffin, and then stored at -80 ℃ or room temperature until use.